This invention relates to a brake shoe for spot-type disc brakes of the type having the friction pad fastened to a steal backing plate.
In brake shoes of the above character, an intimate connection between the friction pad and the backing plate is required in order to permit the friction forces acting upon the friction pad to be absorbed by the backing plate. To achieve this, it is known by the French Pat. No. 1,322,322 to press the friction material onto the backing plate in a plastic state at a temperature of between 100.degree. and 300.degree.C, approximately. In this process, the friction material agglutinates with the backing plate. Further, recesses are provided in the backing plate enabling the friction material to penetrate the backing plate, thus establishing an even more intimate connection with the backing plate. This well-known procedure has the disadvantage that the backing plate forms an undetachable connection with the friction pad so that with each renewal of the individual friction pads in a brake, the backing plates also have to be replaced. In addition, in brake-shoe production the drying process performed in a furnace following pressing of the friction pads onto the backing plates is delayed because the friction pad are covered by the backing plates unilaterally so that the exhaust components can escape from the friction material only via part of the friction surface.
It is further known to rivet the friction pad on the backing plate. However, the holes required in the friction material for inserting the rivets considerably reduce the wearable volume of the friction pad, thus resulting in a shorter life of the friction pad.